BUFFALO, N.Y. – Children’s ear infections cause more
than pain and sleepless nights; they temporarily disrupt hearing
when children are at a critical age for speech and language
development. They also have major social and economic
costs.

But while infants and children receive immunizations against
infections caused by Haemophilus influenzae and pneumococcus, there
is no vaccine against Moraxella catarrhalis, an increasingly
prevalent bacterium that causes at least 10 percent of otitis media
cases.

Now, University at Buffalo scientists, one of just a handful of
researchers in the world studying this organism, have received a
$1.5 million National Institutes of Health (NIH) grant to develop a
vaccine against it. The researchers are among the first tenants in
UB’s Clinical and Translational Research Center, which opened
in September on the Buffalo Niagara Medical Campus.

The goal of the current research, funded by the NIH’s
National Institute on Deafness and Other Communication Disorders,
is to identify new virulence mechanisms for this understudied
pathogen, identify the structure of a candidate antigen for a new
vaccine and develop a new vaccine.

According to Timothy F. Murphy, MD, SUNY Distinguished Professor
of Medicine and Microbiology in the UB School of Medicine and
Biomedical Sciences and principal investigator on the NIH grant,
research on M. catarrhalis has lagged because it was originally
believed to be a “commensal” or harmless bacterium.
While it does cause milder cases of middle ear infections (otitis
media) than other bacteria, Murphy said it is becoming more
prevalent. Preliminary evidence also shows that existing ear
infection vaccines are changing colonization patterns among otitis
media pathogens, possibly increasing the prevalence of M.
catarrhalis infections.

“Of the 15 to 20 million cases of otitis media each year
in the U.S., about 10 percent are recurring, causing incredible
disruption for the child and the family,” explains Murphy.
“When a child has the infection, the middle ear fills with
fluid, a condition that can last for a month or longer. During that
time, the child’s hearing is muffled, which disrupts the
normal development of language and speech skills, potentially
resulting in long-term delays and learning problems in
school.”

Recurrent ear infections also require repeated courses of
antibiotics, which then contribute to the global problem of
antibiotic resistance. Some children must undergo insertion of
drainage tubes under general anesthesia.

“The best option would be to prevent these infections in
the first place,” says Murphy.

The goal of the UB researchers is to identify M. catarrhalis
antigens that are very similar among all strains so that a vaccine
based on a single antigen will protect against as many strains of
the bacterium as possible.

“Based on our results thus far, it looks like we will be
able to identify antigens that are identical or very similar among
all strains and genetic lineages,” says Murphy.

He and his colleagues are using bioinformatics to identify genes
predicted to encode proteins on the surface of the organism,
construct a gene chip to test which of more than 300 possible genes
on the surface are identical or similar among multiple strains and
then clone genes for some of the predicted proteins for testing in
in vitro and mouse models.

The UB group is now testing several promising vaccine antigens
that they have identified. A new vaccine could be ready for human
testing in three to five years.

Murphy and his colleagues at UB are global leaders in the study
of M. catarrhalis in otitis media in children and chronic
obstructive pulmonary disease (COPD) exacerbations in adults. Their
hope is that the same vaccine could be used to prevent both kinds
of infections.

In addition to directing the M. catarrhalis research, Murphy
directs UB's Clinical and Translational Research Center and is
senior associate dean for clinical and translational research in
the UB medical school. For more than a decade, Murphy has studied
how M. catarrhalis causes both otitis media in children and
infections in chronic obstructive COPD in adults.